Abstract

Background

In May 2013, the iTunes and Google Play stores contained 23,490 and 17,756 smartphone
applications (apps) categorized as Health and Fitness, respectively. The quality of
these apps, in terms of applying established health behavior change techniques, remains
unclear.

Methods

The study sample was identified through systematic searches in iTunes and Google Play.
Search terms were based on Boolean logic and included AND combinations for physical
activity, healthy lifestyle, exercise, fitness, coach, assistant, motivation, and
support. Sixty-four apps were downloaded, reviewed, and rated based on the taxonomy
of behavior change techniques used in the interventions. Mean and ranges were calculated
for the number of observed behavior change techniques. Using nonparametric tests,
we compared the number of techniques observed in free and paid apps and in iTunes
and Google Play.

Results

On average, the reviewed apps included 5 behavior change techniques (range 2–8). Techniques
such as self-monitoring, providing feedback on performance, and goal-setting were
used most frequently, whereas some techniques such as motivational interviewing, stress
management, relapse prevention, self-talk, role models, and prompted barrier identification
were not. No differences in the number of behavior change techniques between free
and paid apps, or between the app stores were found.

Conclusions

The present study demonstrated that apps promoting physical activity applied an average
of 5 out of 23 possible behavior change techniques. This number was not different
for paid and free apps or between app stores. The most frequently used behavior change
techniques in apps were similar to those most frequently used in other types of physical
activity promotion interventions.